An agreement reached in Brussels on a new European Union treaty protects Britain's interests, Tony Blair says.
It gives the UK an opt-out on a charter of human and social rights and keeps Britain's independent foreign policy and tax and benefit arrangements.
Gordon Brown, who persuaded Mr Blair to demand protection for the EU's internal market, said he was satisfied.
But the Tories say the pair have signed up to "major shifts of power" and the British public should have a vote.
Mr Blair had gone to Brussels with four "red lines" on human and social rights, foreign policy and tax and benefits which he did not want crossed before a deal could be made.
He said the two days of tough talks had secured all of Britain's four key demands and that the treaty would not require a referendum.
Mr Brown and Mr Blair had several last-minute telephone conversations after the chancellor expressed his unhappiness at a concession to France which had removed a treaty objective of "free and undistorted competition".
Speaking to BBC One's Politics Show, Mr Brown said: "Like every other treaty that has been negotiated - Nice, Amsterdam, Maastricht - while many other people will call for a referendum, it seems to me that we have met our negotiating position.
"Thanks to the negotiating skill of Tony, the four red lines have been achieved and I think people, when they look at the small print, will see that we did what we set out to do, and that was to make sure that in these areas we were properly protected as a country to make our own decisions when we want to do so."
'Major shifts of power'
The new treaty is planned to replace the failed EU constitution, which was rejected by voters in France and the Netherlands in 2005.
Mr Blair said the most important thing about the deal was that it allowed the 27 European nations to move forward.
"The truth is we've been arguing now for many years about the constitutional question," he said.
"This deal gives us a chance to move on. It gives us a chance to concentrate on the issues to do with the economy, organised crime, terrorism, immigration, defence, climate change, the environment, energy - the problems that really concern citizens in Europe."
But shadow foreign secretary William Hague said the government had "absolutely no democratic mandate" to push through the changes that had been made.
"Blair and Brown have signed up to major shifts of power from Britain to the EU and major changes in the way the EU works," Mr Hague said.
"The EU would now be able to sign treaties in its own right and, despite any 'opt-ins', the European Commission and Court of Justice would now have new powers over criminal law."
Mr Hague also said the lack of a referendum on the treaty was a "flagrant breach of a solemn election promise" and that this showed Mr Brown had "no intention of being straight forward" with the people of the UK.
'Stealth and deceit'
Liberal Democrat leader Sir Menzies Campbell said the treaty had not come "cost-free" for Britain.
"By opting out of the Charter of Fundamental Rights, there is now the danger of a two-tier citizenship in the EU," Mr Campbell said.
"Tony Blair has not covered himself in glory with his swansong negotiations in Brussels."
The leader of the UK Independence Party, Nigel Farage, accused Mr Blair of "stealth and deceit".
"The real achievement of this summit - and Tony Blair's helped in this - is that the European Union itself has taken a significant step forward to becoming the global superpower that it always sought to be," he said.
The treaty will need to be ratified by each of the EU's member states at the end of the year, before entering into force in mid-2009.
Mr Blair told reporters he was "absolutely confident" of Mr Brown's support for the agreement, and he did not think there would be any obstacles in finalising the treaty in December.
But some observers in Brussels say the House of Lords may not be keen to play ball when it comes to ratification.